An experimental investigation of an inclined passive wall solar chimney for natural ventilation

Abstract Ongoing investigations into solar chimney development have resulted in constantly evolving new designs. In this study, experiments are carried out with an inclined passive wall solar chimney (IPWSC) model with a uniform heat flux on the active (absorptive) wall. The effectiveness of this design has been examined for the heat flux range of 100 W/m2–500 W/m2 with a fixed base air gap width of 0.1 m and inclination angles of the passive wall in the range of 0–6 degrees. The experimental results show that the inclination angle of the passive wall has no significant effect on the temperature distribution across the air gap width and along the chimney height. On the other hand, the averaged air flow velocity across the air gap width is strongly affected by the inclination angle. The experimental results also show that the IPWSC with 0.7 m absorber height and 0.1 m air gap width at an inclination angle of 6° and input heat flux of 500 W/m2 can produce sufficient ventilation for a 27 m3 room based on ASHREA standards. Further, the present experimental results show that the IPWSC design can significantly improve the ventilation performance of a solar chimney in comparison to the conventional chimney design with vertical passive wall configuration. The experimental results are supported by flow visualization experiments and are consistent with scaling predictions.

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